Why Beginners aren't pointless

Personally I find normal classes far less fun than Beginners.
As for "playing correctly", I'm sure Nexon would've made it impossible for Beginners to level past level 10 if they didn't want people to make such characters.

I fail to see why people keep claiming that I'm having less fun than everyone else.

Because you're driven differently, people are often driven to level up their characters and gain new skills, points, and work twords the next job advance. You're driven for who knows why, but you sure as hell are, some people dont find beginners styles of pressing 1 button to kill things forever that entertaining, not to mention the grind is way harder on one.

People just have their own definitions of fun, if they dont accept beginners into their definition, then theres not much you can do to change their minds.